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N-acetyl-L-cysteine (NAC) is a precursor of cysteine, which is known to increase the level of glutathione (GSH) in the brain. Several neurodegenerative changes linked to oxidative stress take place in the aging brain. This study aimed to assess the neuroprotective effect of NAC supplementation on age-dependent neurodegeneration in the rat brain. Young (4 months) and old (24 months) Wistar rats (n = 6 rats/group) were supplemented with NAC (100 mg/kg b.w. orally) for 14 days. Enzymatic and nonenzymatic antioxidants such as superoxide dismutase and catalase, and GSH and total thiol respectively, prooxidants such as protein carbonyl, advanced oxidation protein products, reactive oxygen species, and malondialdehyde were assessed in the brain homogenates. Furthermore, nitric oxide level, acetylcholinesterase activity, and [Na.sup.+]/[K.sup.+]-ATPase activity were measured and gene expression studies were also performed. The results indicated that NAC augmented the level of enzymatic and nonenzymatic antioxidants with a significant reduction in prooxidant levels in old rats. NAC supplementation also downregulated the expression of inflammatory markers (TNF-[alpha], IL-1[beta], IL-6) and upregulated the expression of marker genes associated with aging (sirtuin-1) and neurodegeneration (neuron-specific enolase, neuroglobin, synapsin-I, myelin basic protein 2) in old rats. The present findings support a neuroprotective role of NAC which has therapeutic implication in controlling age-related neurological disorders.Key words: aging, cytokines, neurodegeneration, N-acetyl-L-cysteine, oxidative stress.La N-acetyl-L-cysteine (NAC) est un precurseur de la cysteine que l'on sait entrainer une augmentation des taux de glutathion dans le cerveau. Plusieurs modifications neurodegeneratives liees au stress oxydatif ont lieu dans le cerveau vieillissant. Cette etude visait a evaluer l'effet neuroprotecteur de la supplementation en NAC dans la neurodegenerescence liee au vieillissement du cerveau chez le rat. Des rats Wistar jeunes (4 mois; n = 6) et ages (24 mois; n = 6) ont recu des supplements de NAC (100 mg/kg de poids corporel) par voie orale pendant 14 jours. Nous avons evalue les antioxydants enzymatiques et non enzymatiques ci-dessous dans des homogenats de cerveau : superoxyde dismutase, glutathion, thiols totaux et prooxydants comme le carbonyle proteinique, les substances proteiques d'oxydation avancee, les derives reactifs de l'oxygene et le malondialdehyde. De plus, nous avons mesure les taux d'oxyde nitrique et procede a des etudes d'activite enzymatique (acetylcholinesterase et [Na.sup.+]/[K.sup.+]-ATPase), ainsi que d'expression genique. Les resultats montraient que la NAC entrainait une augmentation des taux d'antioxydants enzymatiques et non enzymatiques, avec une diminution marquee des taux de prooxydants chez les rats ages. La supplementation en NAC entrainait aussi une regulation a la baisse de l'expression de marqueurs de l'inflammation (TNF-[alpha], IL-1[beta], IL-6), ainsi qu'une regulation a la hausse de l'expression de marqueurs geniques associes au vieillissement (sirtuine-1) et a la neurodegenerescence (enolase specifique des neurones, neuroglobine, synapsine-I, proteines basiques de la myeline 2) chez les rats ages. Les presents resultats viennent appuyer le role neuroprotecteur de la NAC, qui a une incidence therapeutique dans le controle de maladies neurologiques liees a l'age. [Traduit par la Redaction]Mots-cles: vieillissement, cytokines, neurodegenerescence N-acetyl-L-cysteine, stress oxydatif., IntroductionDuring aging, the brain is associated with ultrastructural modifications, biochemical deficits, inflammatory changes, and impairment of memory and cognition, all linked to oxidative stress (Chakrabarti et al. 2011; Pizza et [...]

The present work investigates the propagation of Love wave in a flexoelectric piezoelectric-viscoelastic stratum imperfectly bonded to a piezoelectric-viscoelastic substrate. To study the impact of imperfect interfaces, the non-traditional boundary conditions for two different types of imperfect interfaces have been taken into account. The frequency relation has been obtained in complex form employing a suitable variable separable technique. The dispersion and damping equations of Love wave have been analytically determined in the closed form by separating the real and imaginary part of the frequency relation for two distinct interfaces, i.e., mechanically compliant and dielectrically weakly/highly conducting interfaces in both electrically open and electrically short cases. Numerical calculations are carried out to reveal the impact of the width of stratum, imperfectness parameter, flexoelectric parameters, and flexoelectric loss moduli on the phase velocity and attenuation coefficient of Love wave and are also depicted through graphs for both the interfaces. For validation purposes, the expressions derived as a result of the present study are matched with the standard Love wave equation. [ABSTRACT FROM AUTHOR]

Background: An empyema is the accumulation of purulent fluid in the pleural cavity and complicates pneumonia in 1 of 150 affected children. Symptoms include shortness of breath, fever, dry cough and chest pain. Aims: To evaluate the management of empyema thoracis in children in the COVID era. Methods: We retrospectively reviewed all the patients in our Department admitted between December 2020 to May 2023 who were diagnosed with empyema thoracis and surgically intervened. Results: 22 children with empyema thoracis were treated. All the patients had parapneumonic effusion treated with parenteral antibiotics and chest tube insertion initially but symptoms did not subside. Pre operative imaging included Chest X ray in all the cases and HRCT chest in 16 cases. Four of them underwent Video Assisted Thoracoscopic Surgery (VATS) out of which 2 required conversions to open thoracotomy and 18 patients underwent open thoracotomy primarily. First post operative Chest X Ray was done on POD 1. Chest tubes were removed on post operative day (POD)-4 for VATS and POD 6 for open thoracotomy. One patient treated with VATS and two with Open thoracotomy developed small bronchopleural fistula which was managed conservatively. One patient for whom VATS was converted to open thoracotomy had to undergo prolonged ventilation and expired. Follow up was done for all the discharged patients, all of whom were symptom free and suffered no recurrence. Conclusion: Early surgical management of empyema thoracis in Pediatric population is warranted for curative treatment with low morbidity. [ABSTRACT FROM AUTHOR]